The Common Core gold rush is on. Apple, Pearson, Google, Microsoft and Amplify are all cashing in on the federal standards/testing/textbook racket. But the EduTech boondoggle is no boon for students. It's more squandered tax dollars down the public school drain.

Even more worrisome: The stampede is widening a dangerous path toward invasive data mining.

According to the Silicon Valley Business Journal, the ed tech sector "is expected to more than double in size to $13.4 billion by 2017." That explosive growth is fueled by Common Core's top-down digital learning and testing mandates. So: Cui bono?

In North Carolina, the Guilford County public school district withdrew 15,000 Amplify tablets last fall. Pre-loaded with Common Core apps and part of a federal $30 million Race to the Top grant program, the devices peddled by News Corp. and Wireless Generation were rendered useless because of defective cases, broken screens and malfunctioning power supplies.

Last year, the Los Angeles Unified School District dumped $1 billion of scarce resources into a disastrous iPad program. Educrats paid $678 per glorified Apple e-textbook, pre-loaded with Common Core-branded apps created by Pearson. As I've reported previously, Pearson is the multibillion-dollar educational publishing and testing conglomerate at the center of the federally driven, taxpayer-funded "standards" scheme. Pearson's digital learning products are used by an estimated 25 million-plus people in North America. Common Core has been a convenient new catalyst for getting the next generation of consumers hooked.

Students breached the LAUSD's iPad firewalls and made a mockery of their hapless adult guardians. Despite hefty investments in training and development, many teachers couldn't figure out how to sync up the tablets in the classroom. Taxpayers now realize they were sold a grossly inflated bill of goods, but the district wants to buy even more iPads for computerized test-taking. School officials recklessly plan to use school construction debt-financing to pay for the new purchases.

Los Angeles taxpayer Planaria Price summed up swelling outrage perfectly in a letter to the Los Angeles Times this week: "Cash-strapped LAUSD -- which in 2012 cut libraries, nurses, thousands of teachers, administrators and support staff ... is spending more than $1 billion on one of the nation's most expensive technology programs. ... I would say that 'something is rotten in the state of Denmark,' but few would understand because the teaching of Shakespeare has also been cut."

By its own account, Apple dominates 94 percent of the education tablet market in the U.S. Microsoft is pushing its own Common Core-aligned Surface RT tablet and app suite, along with "Bing for Schools." Rival Google wants in on the game on the taxpayers' dime, too. The company's "Chromebooks," which use a cloud-based operating system mimicking the Google Chrome browser, are gaining market share rapidly. While they are cheaper than iPads, they depend on reliable WiFi. Google offers a suite of Google Apps for Education (GAFE) for "free."

But is this really about improving students' academic bottom line -- or Google's bottom line?

In one school district, the Google devices are used as glorified whiteboards. A recent news article touting Chromebook adoption in Nebraska's Council Bluffs school district described how kindergarteners drew "dots on the rubber-cased tablets clutched in their hands. Then they wrote what they'd done as a math equation: 3 + 3 = 6." No one explained why pencil and paper were insufficient to do the elementary math, other than a teacher gushing that she likes to "mix it up" and provide a "variety of experiences." The district is one of 50 across the country piloting Google Play for Education.

Google is building brand loyalty through a questionable certification program that essentially turns teachers into tax-subsidized lobbyists for the company. The GAFE enrollees are "trained" on Google products. They take classes, attend conferences and hold workshops (some, but not all, funded by Google). After passing GAFE tests, they earn certification. Next, the newly minted GAFE educators open up consultancy businesses and bill their school districts (i.e., the public) to hawk Google's suite of products to other colleagues. And they tell two friends, who tell two friends, and so on and so on and so on.

Google can collect student/family data to target ads through related services outside the GAFE suite, such as YouTube for Schools, Blogger and Google Plus. These are not covered under the already watered-down federal Family Educational Rights and Privacy Act. Under the Obama administration, Grand Canyon-sized loopholes in FERPA have already opened data mining to third-party private entities.

One parent shared her kids' experience with the Chromebooks online: "The biggest problems to date are that kids figured out quickly how to bypass security so they could look at non-approved web material and that kids have problems drawing figures when taking classes such as Chemistry or Physics. ... Many preferred traditional textbooks; others resented the teachers being able to spy on them with the software embedded in the Chromebook."

Another savvy mom noted: "If you think Google won't be handing over any and all data it gets from your kids using their Chromebooks, you're nuts."

Let's be clear: I am not opposed to introducing kids to 21st-century tools. My 13-year-old daughter taught herself Java, HTML and Photoshop. My 10-year-old son mixes music on Logic Pro. I support competent, focused and practical instruction exposing school kids to coding, 3D design and robotics. What I'm against are bungled billion-dollar public investments in overpriced, ineffective technology. Fed Ed's shiny education toy syndrome incentivizes wasteful spending binges no school district can afford.